WAS and blackheart are generally the ones people go for...i'm not positive they will do all the current settings but they should get you close. i believe lights out on impulse-owners still flashes WAS boards.

the universal T board is an option although i dont know if they keep their software up to date or are even still around...
ECS flashing of the cricket boards allowed most of the caps and modes to work but those are getting hard to find. you might be able to make a cable and flash the right version cricket board yourself.
i have an old km2 genesis board that lets the firing rate cap at 10bps so it would get you close.

the old imp stuff is getting pretty dated and its also getting hard to find. hopefully someone else can chime in with some definitive answers.
you could try to search around for manuals/info on the boards i mentioned above. that's about all the imp boards that were made.
I have seen a shocker board put into an impulse...

yea Scenario dreams is still around, talked to damon the other day about installing one in my buddies timmy... if you're nervous about doing the install they could probably do it for you.... the WAS and blackheart have all the modes you'd want, and i believe theres somebody on impulse owners who also flashes ECS boards